Concrete cutting machine



June 6, 1967 SQHUMAN 3,323,507

CONCRETE CUTTING MACHINE Filed Nov. 16, 1964 4 Sheets-Sheet l IN VENTOR.

June 6, 1967 A. SCHUMAN CONCRETE CUTTING MACHINE 4 Sheets-Sheet 2 Filed Nov. 16, 1964 R O T N E V N Q5227 imam/M wry/wi June 6, 1967 A. SCHLIMAN CONCRETE CUTTING MACHINE Filed Nov. 16, 1964 4 Sheets-Sheet 5 INVENTOR.

June 6, 1967 A. SCHUMAN 3,323,507

CONCRETE CUTTING MACHINE Filed Nov. 16, 1964 4 Sheets-Sheet 4 iii l a: 7 INVENTOR.

United States Patent 3,323,507 CONCRETE CUTTING MACHINE Albert Schuman, 19223 Alisa], Covina, Calif. 91722 Filed Nov. 16, 1964, Ser. No. 411,462 7 Claims. (Cl. 125-14 This invention relates to a concrete cutting machine and, more particularly, to an improved portable machine for cutting doors and similar openings in concrete walls, for example.

In the remodeling of concrete or masonry structures, it is often desired that a door or window opening be provided where no opening previously existed. Originally, such openings could be formed only by breaking in the wall with a hammer, either a sledge hammer or a powerdriven hammer. Such methods, however, are time consuming, especially where the opening is to be formed in reinforced concrete, and do not result in neat openings. Accordingly, portable machines for sawing concrete or masonry slabs, such as walls, have been developed to perform this operation faster and more neatly. These machines are characterized by a frame structure of fixed length which is affixed to the surface to be cut. The frame defines a track or guide for a movable carriage to which a saw wheel is mounted. The carriage is manually moved along the guide after the saw has been advanced a predetermined amount into the structure to be cut.

Because the machine must be portable, the frame cannot be excessively heavy. This means that the frame must be relatively short. Since the track defined by the frames of existing machines is no longer than the frame, the cut must be made in several steps if the total length of the cut is longer than the permissible movement of the carriage along the frame. This means that the frame must be moved bodily after each segment of the cut has been made. Accordingly, the frame must be removed from the wall and reaflixed to the wall in a new location. Since a disc saw is used, great care must be taken that the frame is so located in its new position that the saw enters the end of the cut just previously made. It is seen, therefore, that existing devices are also time consuming to use, and a skilled operator is required if proper repositioning of the frame is to be obtained.

This invention provides an improved portable concrete saw for use on concrete or masonry walls and the like. The improved saw is characterized by the feature that the track along which it moves is of indeterminate length. Once the track is located, the cut is made in one continuous operation. The track is in segments which are so constructed to enable rapid, yet accurate, track erection. The saw moves along the track from track segment to track segment under its own power.

Generally speaking, this invention provides apparatus for sawing substantially planar concrete structures. The apparatus includes a guide track which is provided in units adapted to be engaged in end to end relation. Each track unit is adapted for direct connection to the structure to be sawed. A carriage is provided and is equipped with means for mounting it to the guide track for movement along the track. Further, means are operatively engaged between the carriage and the track for moving the carriage along a given track unit and from that unit to the next. A concrete saw is coupled to saw rotating means mounted to the carriage.

The above-mentioned and other features of the invention are more fully set forth in the following description of the invention, the description being presented with reference to the accompanying drawings wherein:

FIG. 1 is a perspective view of a concrete saw according to this invention showing the saw in operation;

FIG. 2 is a front elevation view of a second embodi- "ice ment of a concrete saw according to this invention with certain parts removed for the sake of clarity of illustration;

FIG. 3 is an end view of the saw shown in FIG. 2;

FIG. 4 is a cross-sectional elevation view of the saw drive motor, gear box and the saw mounting;

FIG. 5 is an elevation view showing a plurality of track units according to this invention mounted to a wall or the like;

FIG. 6 is a semi-schematic diagram of the pneumatic system for a concrete saw according to this invention; and

FIG. 7 is a cross-sectional elevation view of the carriage rollers and a rail element.

A concrete wall saw 10 according to this invention, as shown in FIG. 1, includes a track 11 secured to a concrete wall 12, or the like. A carriage 13 is engaged with the track for guided movement along the track. A movable frame 14 is mounted to the carriage for reciprocation toward and away from the wall along a. plurality of guide posts 15. A circular concrete saw 16, preferably a diamond toothed disc saw, is rotated by a motor (not shown in FIG. 1) secured to frame 14. A screw 17 is connected between the frame and a tieplate 18 secured to the end of posts 15 opposite from carriage 135. Rotation of the screw by operation of a crank 19 causes the frame to move along the posts. The screw and crank provide a mechanism for moving the saw 16 and out of engage ment with wall 12.

The features of apparatus according to this invention are more fully shown in FIGS. 2 and 3 which illustrate a concrete wall saw 24 Saw 24} includes a rectangular carriage 21 fitted at each corner with a roller mounting block 22. Each roller mounting block mounts three rollers 23, 24, 25 which engage rail elements 50 and 51 secured to each track unit 11. The track units, the rollers and the roller mountings will be described in greater d tail hereinafter. A small pneumatic motor 26 is mounted to the carriage adjacent one end thereof for driving the carriage along the track. A pair of parallel cylindrical guide posts 27 are mounted at spaced locations to carriage 21. At their ends opposite from the carriage, the guide posts are connected together by a tieplate 28.

A movable saw frame 29 is mounted to posts 27 for movement toward and away from carriage 21. To this end, each guide post is circumferentially engaged "by a pair of journal blocks 30 secured at spaced locations to opposite ends of rame 29. A jackscrew 31 is connected between frame 29 and tieplate 28. The jackscrew includes an externally threaded screw 32 rotatably mounted at one end in a block 33 connected to frame 29 between posts 27. An internally threaded sleeve 33 engages the other end of screw 32. Sleeve 33 is rotatably mounted in a suitable bearing 34 connected to the tieplate. The end of jackscrew 31 opposite from the saw mounting frame is connected to a crank 35. Rotation of the crank in one direction or the other causes the jacksczrew to extend or contract thereby moving the saw mounting frame toward or away from carriage 21. A saw drive motor 37 is mounted to frame 29 substantially centrally of journal blocks 30 and extends away from the frame. On the opposite side of the frame, the motor is connected to a gearbox 38 which, as shown in FIG. 4, has an output shaft 39 to which is keyed a clamp assembly 40 for a disc saw.

A pair of stays or braces 42, preferably provided in the form of angle bars, are connected from between the opposite ends of tieplate 28 adjacent saw clamp it? to the corners of the carriage opposite from saw clamp 40.

As shown in FIGS. 3 and 5, track units 11 are substantially identical to one another. Each track unit includes an elongated rectangular 'bedplate 45. A plurality of substantially identical rectangular lightning holes 46 are provided in the track units. One of the lightning holes 46A, having a length half as long as the other lightning holes, is disposed to open to one end 47 of each track unit. Similarly, the other end 43 of each tack unit defines a lightning hole 46B which has a length equal to one-half the length of holes 36 and which opens to end 48. An insert member 49 is mounted in lightning hole 46B so that when one track unit, say track unit 11A (see FIG. 5), is engaged with another track unit, say track unit 11B, the insert member is snugly engaged in lightning hole 46A of track unit 113. Insert member 49 and the recess defined by lightning hole 46A provides a tongue and groove mechanism for obtaining course alignment of track units 11A and MB. A pair of linear rail elements 50 and 51, preferably provided in the form of steel flat bars, are secured to each track unit along the entire extent of the opposite elongated edges of each bedplate. The ends of the rail elements are coextensive with the ends of the bedplates. As shown in FIG. 7 with respect to rail member 56 each rail member has upper and lower surfaces 52 and 53, respectively, and an outer surface 54. Rollers 23, 24, and 25 are engaged with these surfaces, respectively.

As shown in FIGS. 3 and 7, when the carriage is engage-d with a given track unit, the carriage is movably mounted to the track unit so that the carriage has only one degree of freedom of movement relative to the track unit. This single degree of freedom of movement is along the track unit. The carriage is constrained from movement in all other directions since rollers 23 and 24 engage the upper and lower surfaces of the rail elements and rollers 25 engage the outer surfaces of the rail elements.

To assure that the carriage cannot move toward and away from the wall or other surface to which the track units are mounted, rollers 23, 24 and 25 are mounted to cylindrical axles 56. The axles for rollers 24, however, are engaged in eccentrically bored sleeves 57 which are engaged in holes 58 formed through the corresponding portions of each roller mounting block 22. By moving the sleeve angularly, the axis of rotation of rollers 24 can be moved toward and away from surface 53. This structure provides for maintaining intimate contact between rollers 24 and the rail members regardless of the wear of the rollers and/ or the rail members. Accordingly, the carriage cannot move toward and away from wall 12. Preferably rollers 25 are similarly mounted to the roller mounting blocks so as to prevent lateral movement of the carriage relative to the track.

A rack 59 (see FIG. 5) is mounted to each track unit and extends along the entire length of the track unit. Preferably each rack is mounted to the upper surface of rail member 51. The rack is engageable with a pinion gear 69 mounted to the output shaft (not shown) of carriage drive motor 26. Accordingly, when the carriage is engaged with a track unit, operation of motor 26 causes pinion 60 to rotate and thereby drive the carriage along the track unit. The racks are so arranged that the rack on one track unit continues the rack on the track unit abutted therewith. Accordingly, it is seen that the carriage can move smoothly from one track unit to the next in response to operation of the carriage drive motor.

It was mentioned above that course alignment of two abutted track units is assured by engagement of insert member 49 of one track unit in the recess provided by lightning hole 46A of the other track unit. Fine alignment of abutted track units is provided by a pair of pins 62 carried by track unit 11A, for example, at end 48 and engaged in corresponding holes in end 47 of track unit 1113, for example. Engagement of pins 62 in the corresponding holes assures that the rail members of the abutted track units are colinear and that the racks are suitably aligned with one another.

Each track unit is independently secured to wall 12 which is to be cut by operation of saw or 20. To this end, a plurality of bolting holes 64 is provided through each track unit bedplate. Preferably, the ends of holes 64 which open toward the rail members are countersunk as shown in FIG. 7. The bedplates are bolted directly to the Wall by passing suitable bolts through holes 64 into holes drilled in the wall.

Since most concrete or masonry walls or slabs are not perfectly planar, it is desirable that some mechanism be provided for compensating for non-planarity of the sur- "face to which the track units are affixed, thereby further assuring that the rail elements of abutted track units are colinear. Accordingly, a tapped hole 65 is provided adjacent each bolting hole 64. An externally threaded stud 66 is engaged in each of holes 65. As the bedplate is secured to the wall, studs 66 are adjusted to abut against the wall in such manner that the bedplate lies in a predetermined plane parallel to the generally planar surface of the wall.

Since it is necssary to drill holes in the structure which is having an opening formed therein, it is desirable that the holes which receive the bolts passed through holes 64 by drilled in that portion of the other structure which is to be removed.

FIG. 4 shows a gearbox 38 disposed between output shaft 67 of saw drive motor 37 and saw clamp assembly 40 to enable the apparatus described above to be used with concrete saws of various diameters. Regardless of the diameter of the saw used to cut a concrete structure, the operational peripheral speed of the saw falls within a generally predetermined range. Accordingly, motor 37 is selected so that motor output shaft 67 rotates (When air is supplied to the motor at the rated motor air pressure) at a rate greater than the rotational rate of the smallest saw to be used with the apparatus. The saw motor output shaft 67 defines a pinion gear which is engaged with a reduction gear 68 secured to gearbox output shaft 39. The gearbox output shaft is rotatably mounted in a gearbox housing 70 by suitable ball bearings 69, or the like. A conventional saw clamp assembly 40 is secured to the gearbox output shaft. The larger the saw to be used with motor 37, the greater the speed reduction between shafts 67 and 39. In a presently preferred embodiment of the invention, gearbox 38 is interchanged with another similar gearbox defining a different gear ratio when the diameter of the saw engaged in clamp assembly 40 is changed. It is within the scope of this invention, however, that a single gearbox providing a variable reduction ratio may be used.

Normally the saw engaged in clamp 40 is disposed in a guard 71, as shown in FIG. 1. For the purposes of clarity of illustration, however, the guard has been deleted from FIGS. 2 and 3. A guard bracket 72 is secured to the upper ones of guide post journal blocks 30 for receiving a guard, however.

Pneumatic motors 26 and 37 have been described as components of the foregoing apparatus. It is within the scope of this invention, however, that electric motors may be used if desired. As a portion of the pneumatic control system provided in conjunction with carriage drive motor 26, a pneumatic pressure regulator 75, equipped with a pressure gauge 76, is mounted on a bracket 77 which, in turn, is secured to tieplate 28. The pressure regulator has an inlet fitting 78 (see FIG. 3). A pneumatic reversing valve 79 operated by a handle 80 is secured to bracket 77 below the regulator. As shown in FIG. 6, air is supplied to saw motor 37 through a suitable high pressure air conduit 81 connected directly to saw motor 37. A bypass duct 82 is connected to the duct between duct 81 and inlet fitting 78 of the pressure regulator. The pressure regulator is in turn connected to the reversing valve 79. Suitable pneumatic ducts 83 and 84 are connected between the reversing valve and motor 26. Operation of valve 79 determines which of ducts 83 or 84 has air supplied thereto, thereby controlling the direction of rotation of pinion 60. Preferably air is supplied to the saw motor at a pressure around lbs. per square inch. The pressure regulator is provided for throttling the pressure of the supply air to approximately 20 lbs. per square inch for use with the carriage drive motor.

Preferably a water cooling system for the concrete saw engaged in clamp 40 is provided. Such a cooling system, however, is conventional and, therefore, is not illustrated in the drawing.

There has been described above an improved concrete wall saw. A saw according to this invention is portable and has the feature that a cut of indeterminate length may be made. Prior concrete wall saws, as indicated above, have the disadvantageous feature that the length of the path over which the saw was movable is fixed. As seen from the foregoing description, this restriction is not present in the apparatus described. Moreover, the present apparatus is useful with circular saws of various diameters.

While the invention has been described above in con junction with specific apparatus, this has been by way of example only and is not to be considered as limiting the scope of the invention.

What is claimed is:

1. Apparatus for sawing concrete structures including non-horizontal and vertical structures comprising track means comprised of a plurality of substantially identical elongate units adapted to be engaged in end-to-end relation to each other to define a guide substantially continuously along the track means, each unit being adapted for connection directly to a structure to be sawed and including an elongate bed plate having opposite side edges, a top surface and a planar base surface, a rail flange defining top, bottom and side guide surfaces secured to the bed plate top surface along each side edge thereof proximate to the base surface and extending laterally of the adjacent side edge, the rail flanges being essentially parallel to the bed plate base surface and spaced parallel from each other transversely of the bed plate, a carriage, carriage mounting means for mounting the carriage to the rail flanges for constrained movement along the track means, the mounting means including upper, lower and side rollers engaging the respective rail guide surfaces and means depending from the carriage into close proximity with the bed plate base surface for rotatably mounting said rollers to the carriage, means for moving the carriage along a given unit and from unit to unit including a rotatable' element mounted to the carriage for engagement directly with the adjacent unit of the track means, a disc saw, motor means mounted to the carriage for rotating the saw in a plane normal to the plane of the bed plate base surface of the adjacent track unit, and means for adjusting the depth of cut produced by the saw.

2. Apparatus according to claim 1 wherein each track unit includes a rack extending along the unit parallel to the rail flanges, and the rotatable element comprises a pinion gear.

3. Apparatus according to claim 1 including a motor connected to the rotatable element for rotating the same for self-propelling the carriage along the track means.

4. Apparatus according to claim 1 wherein rollers are mounted on axles carried by the carriage, at least some of the axles being adjustable angularly relative to the carriage about their axes, and the rollers carried by said adjustable axles are mounted to said axles for rotation about axes eccentric to the axes of said axles.

5. Apparatus according to claim 1 including means for aligning adjacent track units relative to each other so that adjacent units are colinear.

6. Apparatus according to claim 5 wherein the aligning means includes a projection at one end of each track unit and a recess at the other end of each unit configured to mate with the projection on the one end of the adjacent unit.

7. Apparatus according to claim 1 wherein the carriage includes a pair of spaced parallel posts mounted adjacent the saw and extending from the carriage in a common plane parallel to the plane of rotation of the saw, a frame slidably engaged with the posts for guided movement therealong and mounting the saw, means for moving the frame along the posts, and brace means rigidly connected from the ends of the posts opposite from the carriage to the carriage opposite from the saw.

References Cited UNITED STATES PATENTS 1,411,864 4/1922 Mitrovich. 2,075,369 3/ 1937 Stetler 51180 2,079,864 5/1937 Lansing -14 2,766,511 10/ 1956 Lamoureux 29-70 2,965,094 12/ 1960' Carrier 125-14 3,011,530 12/1961 Lamb 143-47 FOREIGN PATENTS 146,584 5/ 1952 Australia.

HAROLD D. WHITEHEAD, Primary Examiner. 

1. APPARATUS FOR SAWING CONCRETE STRUCTURES INCLUDING NON-HORIZONTAL AND VERTICAL STRUCTURES COMPRISING TRACK MEANS COMPRISED OF A PLURALITY OF SUBSTANTIALLY IDENTICAL ELONGATE UNITS ADAPTED TO BE ENGAGED IN END-TO-END RELATION TO EACH OTHER TO DEFINE A GUIDE SUBSTANTIALLY CONTINUOUSLY ALONG THE TRACK MEANS, EACH UNIT BEING ADAPTED FOR CONNECTION DIRECTLY TO A STRUCTURE TO BE SAWED AND INCLUDING AN ELONGATE BED PLATE HAVING OPPOSITE SIDE EDGES, A TOP SURFACE AND A PLANAR BASE SURFACE, A RAIL FLANGE DEFINING TOP, BOTTOM AND SIDE GUIDE SURFACES SECURED TO THE BED PLATE TOP SURFACE ALONG EACH SIDE EDGE THEREOF PROXIMATE TO THE BASE SURFACE AND EXTENDING LATERALLY OF THE ADJACENT SIDE EDGE, THE RAIL FLANGES BEING ESSENTIALLY PARALLEL TO THE BED PLATE BASE SURFACE AND SPACED PARALLEL FROM EACH OTHER TRANSVERSELY OF THE BED PLATE, A CARRIAGE, CARRIAGE MOUNTING MEANS FOR MOUNTING THE CARRIAGE TO THE RAIL FLANGES FOR CONSTRAINED MOVEMENT ALONG THE TRACK MEANS, THE MOUNTING MEANS INCLUDING UPPER, LOWER AND SIDE ROLLERS ENGAGING THE RESPECTIVE RAIL GUIDE SURFACES AND MEANS DEPENDING FROM THE CARRIAGE INTO CLOSE PROXIMITY WITH THE BED PLATE BASE SURFACE FOR ROTATABLY MOUNTING SAID ROLLERS TO THE CARRIAGE, MEANS FOR MOVING THE CARRIAGE ALONG A GIVEN UNIT AND FROM UNIT TO UNIT INCLUDING A ROTATABLE ELEMENT MOUNTED TO THE CARRIAGE FOR ENGAGEMENT DIRECTLY WITH THE ADJACENT UNIT OF THE TRACK MEANS, A DISC SAW, MOTOR MEANS MOUNTED TO THE CARRIAGE FOR ROTATING THE SAW IN A PLANE NORMAL TO THE PLANE OF THE BED PLATE BASE SURFACE OF THE ADJACENT TRACK UNIT, AND MEANS FOR ADJUSTING THE DEPTH OF CUT PRODUCED BY THE SAW. 